Interference of dentofacial deformities in the acoustic characteristics of speech sounds

Abstract

ABSTRACT Purpose: to verify speech characteristics regarding the production of fricative sounds in people with dentofacial deformities (DFD), through acoustic analysis, evaluating possible interferences of the variation of the osseous bases in the articulation of speech. Methods: fifteen adults of both genders, aged between 17 and 42, participated in the study. They were distributed in three groups: GII (n = 5) Skeletal Class II, GIII (n = 5) Skeletal Class III, and CG (n = 5) without DFD. All of them had their voices recorded, with key words containing the fricative sounds of Brazilian Portuguese (BP), and acoustically analyzed; the parameters: duration, intensity, and formants F1, F2. The Mann-Whitney test was used to compare the groups. Results: there were differences (p <0.05) when comparing GII and GIII with CG. For the variable duration GIII obtained higher value in the fricative sound /z/ (r = 0.016, p <0.05). The variable intensity was higher for GII in /z/ (r = 0.028, p <0.05), and higher for GIII in /f/ (r = 0.028, p <0.05), /v/ (r = 0.028, p<0.05) and /ʃ/ (r = 0.036, p <0.05). For the variable F1, GII obtained a higher value for the syllable /za/ (r = 0.047, p <0.05). In the variable F2, GII obtained the lowest value in the syllable /ʒa/ (r = 0.047, p <0.05). Conclusion: the disharmony of the maxillomandibular osseous bases results in interference in speech acoustic characteristics regarding fricative sounds.